neilestrick

pir, there is one other thing that you should consider.   how tall are you and how far down into the kiln you buy can you reach?   can you load shelves and pots easily today?   for 20 or thirty years in the future?  
L&L  now makes one that is wider than it is tall.   i wish i had one.   at 82 i find putting things on the bottom shelf, which is raised off the bottom of the kiln by 2 inches, is getting difficult.  if you are going to pay for a new kiln, remember how long they last with reasonable use.   notice when you see one close up that your fingernail will indent the brick if you just push your finger in.   and yes, the new discussions of kiln size talk about cubic feet.   ignore that and get the depth and width and shelf size. that is what matters.  the size of an acre is 43,560 square feet.  the shape matters, you cannot build a house on a 2 foot wide by 21,780 feet long acre.
L&L makes an easy to maintain kiln, those hard brick channels saved the day often when i unloaded a heavy shelf and smacked the wall.
to learn about kilns look at your local library section on pottery.   lots of junk about collecting old stuff, avoid that and get to the ones that are textbooks.  there is a very complete list somewhere in the archives here.

That is a great looking  job on venting the basement window.   I didn't have any windows when I had my basement studio (dungeon) but I did have a dryer vent that went outside.  My husband reconfiqured the vent to where I could run a  a  vent to it when I fired.   He installed a baffle that I could use to block the main vent off to the dryer while firing.  When your house is 100 years old and it has a double brick  twelve inch thick wall  you have to be creative.    Denice

Shouldn't be a problem. The temperature change won't be extreme or fast enough to cause a problem, and freezing is only an issue when water is involved. If the clay body isn't sufficiently vitrified and absorbs moisture and then freezes it can crack, or in the case of a planter, if the wet soil freezes and expands it can crack the pot. You won't be in either of those situations at the market so you'll be fine.

This. It takes forever for sealed forms to dry completely. The outside can be bone dry but the inside will still be leather hard. It  also takes longer for the heat of the kiln to penetrate and drive off the last bit of moisture, so do a good long preheat and ramp slowly at first.

HERE is a good PVC size chart. Different types of pipe are measured differently- some by ID some by OD. They all come in various thicknesses as well.

If you want to paint images like flowers and whatnot, then you want to use underglazes, not glazes. Glazes will generally run/flow where they contact each other, and any imagery you paint on will bleed and move and blur. Glazes do not require a clear glaze over them, and the clear glaze will mix with the other glaze and change how it looks. Underglazes, however, will not bleed where they contact each other, are not fluid, and have the added benefit of being the same color before and after firing so they're easy to work with. Underglazes require a glaze over them in order to be durable and food safe.

Finishing the bottom of a pot is a necessary step in the process, just like throwing and glazing, and all three steps are equally important to the success of the work. Finishing the bottom can be very involved like trimming a fancy raised foot, or it may be very simple like just rolling the foot on the table to smooth out the corner. Whatever method you choose, it needs to be done well and the results should enhance the pot. Too many people see trimming as an annoyance that has to be tolerated rather than mastered- everyone wants to put all their effort into mastering throwing. Mastering trimming  will make one a better potter just like mastering throwing and glazing, and to me that means mastering all aspects of trimming, including centering and anchoring your pots. The Giffin Grip works great for some types of pots, but not so much for others, so learning other techniques is absolutely necessary.
As I said in my original post, if you want to use a Giffin Grip then go for it. If it works for you, great, nobody is stopping you! But I do not allow them in my studio because it is my job as an instructor to lead my students to mastery, and that does not involve using a GG. And I can assure you that my students appreciate that and are making beautiful work despite my tyrannical methods. If you would like to open your own studio and rent Giffin Grips to your students, then by all means do it, and good luck.

If you're adding to moist clay, you're going to have the mix the heck out of it in order to get good dispersal of the neph sye, especially since you're adding such a small percentage. I would definitely mix the neph sye with water and hit it with a blender so there are no chunks before adding it to the body.

There will always be some leakage around the lid. Totally normal. Best not to mess with loose fiber unless you really need to.

Good point, the previous owner said she stuffed ceramic fiber in the rim actually - I think heat was coming out by the handle. Ty again! Also thank you for the questions you’ve answered in another thread I found about troubleshooting this kiln - I see I’m potentially in for it…  

120/125 volts are the same thing. The difference between this plug and regular household plug is that the kiln has a 20 amp plug, , whereas most household outlets are 15 amps. You can only plug it into a receptacle that is wired for that amperage. You'll need to have an electrician upgrade the wires and outlet for whatever receptacle you plan to use. Code requires that the kiln be on a breaker that is 25% greater than the draw of the kiln, so it should actually be on a 25 amp circuit and have a 30 amp power cord and plug on it.

Overbuild the stand. Any flexing of the metal will result in cracking of the floor slab, so make it really, really stiff. Use casters that are hard enough that they won't flatten when the kiln is just sitting there. Polyurethane wheels can develop flat spots, and the heat from the kiln can exacerbate the flattening. Steel or hard plastic casters are a better choice.

The hole in the lid is probably bigger than you need. Plug it. Most kilns are leaky enough that they don't really need holes in the lid, so I would try it without making any holes first, you can always add them later.

Just to add, all the above is correct and I believe that circuit needs to be exclusive to the kiln, so not only breaker sized and wire sized  correctly, dedicated for the kiln which means other receptacles are not connected to that circuit. So your electrician should actually do a number of things, including pulling a separate circuit for the kiln.

@Lola Rosier If you need to vent both heat and fumes, then go with an overhead hood, like the one Vent-A-Kiln makes. If you have a low ceiling get the wall mounted swing arm. If you're only worried about fumes then get a downdraft vent. The Orton vent is really cheap on Amazon right now. I'm not a big fan of the spring mounted cup since it can be difficult to get it to sit evenly against the bottom of the kiln and can easily be knocked out of alignment, so I prefer to screw the cup to the side of the kiln near the bottom. From a safety standpoint either one is a good choice. If you have a window and a fan that can bring cool air into the space, get the downdraft and use the window for cooling since the downdraft will be half the price of the hood.

Overbuild the stand. Any flexing of the metal will result in cracking of the floor slab, so make it really, really stiff. Use casters that are hard enough that they won't flatten when the kiln is just sitting there. Polyurethane wheels can develop flat spots, and the heat from the kiln can exacerbate the flattening. Steel or hard plastic casters are a better choice.

Overbuild the stand. Any flexing of the metal will result in cracking of the floor slab, so make it really, really stiff. Use casters that are hard enough that they won't flatten when the kiln is just sitting there. Polyurethane wheels can develop flat spots, and the heat from the kiln can exacerbate the flattening. Steel or hard plastic casters are a better choice.

Overbuild the stand. Any flexing of the metal will result in cracking of the floor slab, so make it really, really stiff. Use casters that are hard enough that they won't flatten when the kiln is just sitting there. Polyurethane wheels can develop flat spots, and the heat from the kiln can exacerbate the flattening. Steel or hard plastic casters are a better choice.

Overbuild the stand. Any flexing of the metal will result in cracking of the floor slab, so make it really, really stiff. Use casters that are hard enough that they won't flatten when the kiln is just sitting there. Polyurethane wheels can develop flat spots, and the heat from the kiln can exacerbate the flattening. Steel or hard plastic casters are a better choice.

@Catatonic The switch is just an infinite switch. According to the Duncan manual, when you turn it on, it will go on low for 2 hours, then switch over to whatever cycle you've set the dial to. Overglaze is like medium, Ceramic is like med-high, High Fire is full on. Try this: start with the switch off, push the power button on the sitter, turn the switch to Overglaze and let it go 4 hours, then switch to Ceramic for 4 hours, then to High Fire until it's done. It may shut off on the ceramic setting.

If you plan to glaze fire to cone 6 (2230F), then you want a kiln that can fire to cone 10. That way your elements can wear quite a bit before they need to be replaced. A cone 10 kiln will get about 40% more element life than a cone 8 kiln when firing to cone 6.
You order the kiln according to the electrical service in the building. You can run a single phase kiln in a building that has 3 phase service. You cannot run a 3 phase kiln in a building that only has single phase service.
There is no good reason to buy a manual kiln. Get a digital kiln, and get the new touch screen controller. They're easier to program than the old controllers, are more user-friendly for custom programs, and make diagnosing problems a lot easier.
It's not a bad idea to have a small kiln for testing or small batches, and a larger kiln for producing work. You have to have the proper electrical circuit run for each one, though, so buying a small kiln now and a larger one later can get expensive in electrician costs.
I would not buy anything until you know where you're going to put it. The electrical requirements are different for every kiln, so you first have to make sure that the electrical system in your building can handle the kiln you want.
 

I'm definitely not that handy!

Used kilns are always an option, you just need to make sure the bricks are in good shape. Everything else can be replaced fairly easily if you're somewhat handy. Manual kilns can be converted to digital, but expect to spend about $1000 to do so.

IMO venting is required. A downdraft vent will increase the life of your elements and generally make glazes look better, in addition to saving your lungs. Even if you're not in the room, all that tiny particulate matter that's in the fumes will be landing all over everything in your studio, which isn't good. A downdraft vent only vents fumes, though, so depending on your setup you may also need a way to vent the heat coming off the kiln. That could be as simple as cross-ventilation between two windows, or a fan in a window near the kiln. Vent-A-Kiln makes a great overhead hood that pulls out heat and fumes, and is a good option if you need both. Vents need a path to outdoors, so that may mean drilling a hole in the wall or roof, of you can rig up a board in a window, either temporary or permanent.  Sliding windows are easy to fit a plywood board into when the vent is in use. For a permanent setup you can remove the window sash completely and install a board. Here's an example of a semi-permanent board that's wedged tight against the window frame, with weatherstripping between them for a good seal:

When we look at the power that a kiln has, we look at the wattage. For instance, a Skutt KM1027-3 or L&L e23T-3 on 240 volt service pulls 11,520 watts whether it's on single or 3 phase. Watts are what you pay for, so the cost of firing will be the same whether on single or 3 phase. Where the difference comes in is that 3 phase allows you to achieve that wattage with lower amperage. A typical breaker box can handle up to 200 amps, so on 3 phase you can hook up more stuff before you max out the box. A kiln that will pull 48 amps single phase service will only pull 28 amps on 3 phase since you're diving the pull between 3 wires instead of just 2. So if you were hooking up multiple kilns you could do 3 kilns on 3 phase and use fewer amps than 2 kilns on single phase.
The math from single to 3 phase is to divide the single phase amperage by the square root of 3 (1.73). 
Another place you'll see a benefit of 3 phase kilns is in some 10 cubic foot kilns that are meant to be plug-and play (don't need to be hardwired). In order for a kiln to have a plug it has be under 50 amps. If you look at the Skutt KM1227-3 or the L&L e28T-3, they pull 48 amps on 240 volt single phase service, which means they only have enough power to get to cone 8. But 50 amps gives you lots of room to add more power on 3 phase service, so L&L takes their 240 volt 3 phase kiln and bumps it up to 16,600 watts, which is only 40 amps on 3 phase, which gives it more than enough power to get to cone 10.
3 phase power can be less expensive and easier to install because the lower amperage allows for smaller wires, disconnect boxes, fuses, etc. So to answer your question, yes, get 3 phase is if it's available.